Grinding wheel dresser



Aug. 5, 1947. F. .LjHNKEL 2,425,095 4` GRINDING WHEEL D RESSER FiledDec. 29, 1945 2 Sheets-Sheet l l Aug' 5, 1947- F. J. HENKEL 2,425,095

GBINDING WHEEL DRESSER' Filed Dec. 29, 1945 2 Sheets-Sheet 2 Patentedug. 5, 194'? GRINDING WHEEL DRESSER.

lFerdinand J. Henkel, 'Royal-"Oak, Mich., assigner to Lamina Diesand-Tols,-'Inc.,\Berkley,Mich.,

a corporationof Michigan Applicationlecember 29, 1945,4SerialNo.\.637,847

-9 Claims. 1 This invention relates Ato grinding machines, and inparticular to wheel dressing devices for such-machines.

`One object isto :provide a simple yet accurate grinding wheel dresserwhereinthe dressing tool may-be instantly attached or removed merelybyplacing'it on a swinging rest carrying a template. Another object is `toprovide a grinding wheel dresser wherein the dressing tool lis carriedin a-holder which rests upon a baseplate and in contact with ya templateas it is pushed manually across the face ofthe grinding wheel.

Another object is to provide a grinding .wheel dresser as set forth invthe 'preceding objects wherein the rest is moved toward and .awayffromthe grindingwheel byra micrometer screw mechamsm.

'Another object is'to provide a grinding wheel dresser 'as 'set forth inthe preceding objects wherein the ,holder carrying Athe ydressing tool.is held in lposition against the rest and likewise against the templateby a combination ofgravity and manualforcegthe absence of other mecha'-nism inthe grinding wheel area enabling the rest andV template .tobetkept scrupulously clean and to 'be-free from `the errors otherwiseAarising in mechanism exposed t0 the .grit thrown oi bythe grinding wheelbeing` trued.

-Anotherlobject is to provide aggrinding wheel dresser Yas -set forth in'the preceding objects wherein the rest Aswings about a pivot shaft11ocated-above-the'dressing area so that grit thrown off by 'theVgrinding wheel will never reach the bearings ofthe pivot shaft andhence Ythellatvter will -retain lits l'accuracy of Aadjustment withoutthe Wear otherwise occurring in such devices.

Another yObjectis to provide a grinding machine idresser as setforth inthe preceding objects wherein a modified form ofthe invention provides arest which isinclined to the horizontalin the dressing position of thedevice.

Other objects and advantages will becomeapparent during the course ofthe followingdescriptionof the accompanying drawings wherein:

'Figure 1 is a toplplan view of a grinding `wheel dresser .according `toa preferred embodiment of theinvention;

Figure 2 is :a .side elevation, partly in section,

of the grinding .wheeldresser shown 'in Figure 1 Figure-Sisan endelevation ofthe micrometer hand wheel .and adjacent mechanism -in theupperleft-handcorner of Figure i1;

Figure `i is a vertical section taken alongthe brckenline 4 4 n'Figurel;

Figure 5 .is 'a vertical cross-section 'taken along the line 5-5inEligure 2 'Figure is a horizontal section, partly in top plan view,taken approximately along the `line 6-."6 inFigureZ;

Figure 7 is a .fragmentaryvertical section of the dressingtool block andswinging base plate taken along .the line 'I-ll inFigure 2.; 'and-Fgigure .18 is a side elevation similar to lFigure Zibutshowing amodification vthereof Aemploying an' inclined base plate.

Referring rto 'the drawings jin detai1, Fig ures l aIIdZ showapreferredienibodiment ofthergrinding Vwheel dresse-r of this invention,generally designated l0, as applied to ,a .conventional grindingmachine, generally 'designated `Il and havingthe usuaigrindinglhead |12with. a forwardlynprojecting bearing 'bracket .I3 containing the usualbore 'h1 rotatably Supporting a -shaft l5. Theshaftflisprovided with aflange i6 .having a surface .t1 serving as anabutmentfora grindingwheel'l 8 mounted upon the reduced diameter portion L9 ofthe shaft l5 andheldimposition by a washer'Z retained' by a nut '2| threaded upon a furtherreduced diameter portion 22 4which carries .a thread :corresponding tothat ofthe,` nut 2|. The grinding vwheel I|.8 Ais provided with theusual peripheralsur'faceZS which is tobe .trued 0I' dressed bythetgrin'ding wheel dresser. I l)v of the present invention.

`The grinding .head I2 is -provided .with a plurality of threadedlholesZA (Figure i) :adaptedto receive boltsZSpassIlgthrough bores 26inthe base portion I2 of `a 'bracket vi28 (Figure 4) and having amachined rear surface 29 engaging the similarly machined .abutmentsurface .30 Aof the grindingheadlZ (Figure 1). The base portion-2l ofthe bracket '28 is approximately .annularin shape and is provided `with.a central aperture 3'lifor thepassage of ,the-bearing-bracket i3, ,Apart 32 V( ligure 4) of thebase :poi-tion :.21 is cut away in thedirection of a chord ofthe base portion .27 ,and termnates'nastangentiallydisposed arm'33 .extending outwardly from. the base:portion 21.

`'lhe arm 33 of the bracket 28 is provi-ded .with elongated angled guidesurfaces l3.5: (Figures .4 and 5) engaging similarly angled surfaces v35of retaining vplates-36 of a dove-'tailed slide, generally designatedA3l. The .dove-.tailed slidel further 'includes a carriageilikeplatekhaving threadedfholesl therein adapted to receivebolts passingthroughholes 4lV in the retaining plates 36,-thereby causingthe elements 3.6,'38 and .40 to travel .to and Lfro relatively to the arm 33 along 3 theangled guide surfaces 34 thereof. The bolts 40 also serve to provide anadjustment and takeup for wear in the dove-tailed slide 31 and tomaintain the latter in a high precision operating condition.

The slide 31 is moved to and fro along the arm 33 by means of a nut 42(Figure 6) movable to and fro in an elongated recess 43 in the arm 33along a screw shaft 44 threaded through the threaded bore 45 of the nut42. The latter is' approximately T-shaped (Figure 6) and is pro" videdwith a shank 46 secured as at 41 in a transverse hole 48 in the plate38.

The screw shaft 44 is provided with a flanged portion 49 (Figure 6)located in a recess 50 connected to the recess 43 by an enlarged bore 5|so as to permit free rotation thereof. The recess 43 at its opposite endterminates in a cavity 52 adjacent the free end of the screw shaft 44.

Beyond the iianged portion 49, the screw shaft 44 is provided with areduced diameter portion 53 passing through a corresponding bore 54 in acircular head 55 bolted as at 56 (Figure 3) to the end 51 of the arm 33.The head 55 is provided with a cylindrical boss 58 (Figure 6) which isencircled by the rim 59 of a hand wheel 60 keyed as at 6| to the outerend of the reduced diameter portion 53 of the screw shaft 44. A button62 additionally serves to retain the hand wheel G upon the end of thescrew shaft 44 and secured thereto by the screw 63 threaded into thehole 04. The hand wheel flange 65 is provided with an eccentric threadedhole 66 into which is threaded the end of a knob or handle 61 forrotating the hand wheel 60. The rim 59 is provided with graduations 68of any suitable dimension, such as in thousandths of an inch. Thesegraduations 98 cooperate with a zero pointer 69 to indicate the travelof the slide 31 and accordingly the feed imparted thereto. The screwshaft 44 is provided With anti-friction thrust bearing assemblies and 1|(Figure 6) on opposite sides of the head 55 and surrounding the reduceddiameter portion 53 of the screw shaft 44.

Secured by the bolts 12 passing through holes 'i3 in the plate 38, is atubular hanger 14 having threaded holes therein (Figure 6) for receivingthe ends of the bolts 12. The hanger 14 is provided with a bore 16(Figure 2) having annular bearing recesses 11 and 18 at its oppositeends for receiving anti-friction bearing assemblies 19 and 80respectively. The outer race of the bearing assembly 80 is held inposition by a cylindrical cap 8| bolted as at 82 to the hanger 14.

The inner races of the bearing assemblies 19 and 80 are mounted at theopposite ends of the reduced diameter portion 83 of a pivot shaft 84,the lower end of which is threaded as at 85 to receive a retaining nut86. The upper end of the shaft 84 is enlarged as at 81 to receive a bore88 in the hub 89 of a swinging arm 90, the shaft 84 being enlarged as at9| to engage a countersink 92 (Figure 2) in the hub 89. The hanger 14and shaft 84 are inclined upwardly relatively to the slide 31.

The arm 90 is provided with a plate-like depending portion 93 of roughlytriangular shape having a transverse bore 94 (Figures 6 and 7 in whichis secured a stop screw 95 having a head 95 engaging the adjacentsurface 91 of the slide 31. By this means, thearm 90 is accuratelylocated in a vertical position relatively to the slide 31. Secured tothe bottom edge 98 of the depend- 4 img portion 93 of the arm 90 is aplate-like tool rest 99, the connection being made by bolts |00 passingthrough holes |0| therein into the threaded holes |02 formed in the edge98'.

The upper surface |03 of the rest 99 is accurately machined to atnessand carries a template bar |04 secured thereto as by the bolts |05threaded into the holes |00 therein. The template bar |04 has secured toa vertical edge thereof a template |01 having an accurate contactsurface |08 engaged by the correspondingly accurate front surface |09 ofa contact strip ||0 secured to the dressing tool holder in the form of ablock (Figure 1). The dressing tool holder has an accurately machinedbottom surface ||2 adapted to rest upon and slide along the uppersurface |03 of the rest 99. The contact surface |08 of the template |01may be straight or curved or otherwise configured, depending upon theconfiguration of the grinding wheel |8, a straight template being shownmerely for purposes of illustration.

The tool holder in its front face ||3 is provided with a socket ||4 inwhich is mounted the shank ||5 (Figure 1) of a diamond dressing tool IIBhaving a diamond or other extremely hard cutting element ||1 mounted inthe forward end thereof. The diamond tool I6 is held in position by theset screw ||8 threaded into the transverse hole ||9 (Figure 1). Theparts are so arranged and dimensioned that the diamond ||1 is positionedin alignment with and approximately at the end of a horizontal diameterof the grinding wheel |8.

The modification shown in Figure 8 is similar to the preferred form ofthe invention shown in Figures l to 'l inclusive, except that thebracket 28 is mounted on the grinding head |2 in an inclined directionsuch that the rest surface |03 of the rest 99 is inclined to thevertical, thereby causing the tool holder to be similarly inclined, andthe diamond ||1 to be aligned with an inclined diameter of the grindingwheel |8. By this construction the tool holder is urged downwardly bygravity against the template |01.

In either form of the invention, when the wheel dresser is not in useand the grinding machine is being used, the tool holder k| is removedfrom the rest 99 and stored in a safe location. The arm is then swungupwardly around its pivot shaft 84 until it is out of the way, as shownby the chain lines in Figure 8. In the form of the invention shown inFigures 1 to 7 inclusive, the arm 90 will occupy a similar locationrelatively to the carriage 38 and arm 33, but more nearly horizontal inits position.

In the operation of either form of the invention, when it is desired todress or true the peripheral surface 23 of the grinding wheel I8, thearm 90 is swung from its raised to its lowered position, as determinedby the engagement of the head 96 of the stop screw 95 against thesurface 91 of the dove-tailed slide 31. The dress,- ing tool holder isthen placed upon the upper surface |03 of the rest 99, which haspreviously been carefully wiped off, and pushed forward until itscontact strip |09 engages the template |01 at a location to one side ofthe grinding wheel I8. The hand wheel E0 is then turned to move theslide 31 the necessary amount to bring the diamond |1 into closeproximity to the grinding wheel surface 23 for a suitable depth of cut.The grinding wheel |8 is then rotated and the tool holder moved alongthe template |01 While being held firmly in the operators hand, therebytaking a cut across the peripheral surface 23" of the grinding wheellli. The hand wheel 60 is then moved a prescribed amount according tothe graduations 68 with reference to the Zero pointer 69 to move theslide 3l to take the second cut across the periphery 23 of lthe grindingwheel I8. This procedure is repeated until the periphery 23 is suitablytrued.

While I have shown and described my invention in detail, it is to beunderstood that the same is to be limited only by the appended claims,for many changes may be made without departing from the spirit and scopeof my invention.

What I claim is:

1. A wheel dresser for grinding machines comprising a support attachableto the grinding machine, a rest connected to said support and extendingadjacent said wheel, a template mounted on said rest, a wheel dressingtool holder slidably supported on said rest in engagement with saidtemplate, and a wheel dressing tool mounted on said tool holder, saidrest being 4'positionable in an inclined arrangement relatively to saidwheel, and said tool holder being urged by gravity down said inclinedrest into engagement with said template.

2. A wheel dresser for grinding machines comprising a support attachableto the grinding machine, a slide reciprocable on said support, means forprecisely moving said slide Itoward and away from said wheel, a restmovably mounted on said slide and extensible into a position adjacentsaid wheel, a template mounted on said rest, a wheel dressing toolholder slidably supported on said rest in engagement with said template,and a wheel dressing tool mounted on said tool holder.

3. A wheel dresser for grinding machines cornprising a supportattachable to the grinding machine, a slide reciprocable on saidsupport, means forl precisely moving said slide toward and away fromsaid wheel, a rest pivotally mounted on said slide and extensible into aposition adjacent said wheel, a template mounted on said rest, a wheeldressing tool holder slidably supported on said rest in engagement withsaid template, and a wheel dressing tool mounted on said tool holder.

4. A wheel dresser for grinding machines comprising a support attachableto Vthe grinding machine, a slide reciprocable on said support, meansfor precisely moving said slide toward and away from said wheel, a pivotmounting arranged on said slide, a rest connected to said pivot mountingand swingable therearound into and out of proximity to said wheel, atemplate mounted on said rest, a wheel dressing tool holder slidablysupported on said rest in engagement with said template, and a wheeldressing tool mounted on said tool holder.

5. A wheel dresser for grinding machines comprising a support attachableto the grinding machine, a slide reciprocable on said support, means forprecisely moving said slide toward and away from said wheel, a pivotmounting arranged on said slide, a rest connected to said pivot mountingand swingable therearound into and out of proximity to said wheel, atemplate mounted on said rest, a Wheel dressing tool holder slidablysuppor-ted on said rest in engagement with said template, and a wheeldressing tool mounted on said tool holder, said pivot mounting havingits pivot axis inclined upwardly relatively to said wheel.

6. A wheel dresser for grinding machines comprising a support attachableto the grinding machine, a slide reciprocable on said support, means forprecisely moving said slide toward and away from said wheel, a pivotmounting arranged on said slide, a rest connected to said pivot mountingand swingable therearound into and out of proximity to said wheel, atemplate mounted on said rest, a wheel dressing tool holder slidablysupported on said rest in engagement with said template, and a wheeldressing tool mounted on said tool holder, said pivot mounting havingits pivot axis inclined upwardly relatively to said wheel and said restdepending therefrom toward said wheel.

7. A Wheel dresser for grinding machines comprising a support attachableto the grinding machine, a slide reciprocable on said support, means forprecisely moving said slide toward and away from said wheel, a pivotmounting arranged on said slide, a rest connected to said pivot mountingand swingable therearound into and out o-f proximity to said wheel, atemplate mounted on said rest, a wheel dressing tool holder slidablysupported on said rest in engagement with said template, and a wheeldressing tool mounted on said tool holder, said pivot mounting havingits pivot axis inclined upwardly relatively to said wheel and said restdepending therefrom toward said wheel, said rest and said tool holderhaving relatively flat contacting portions arranged for slidableengagement therebetween.

8. A wheel dresser for grinding machines comprising a support attachableto the grinding machine, a slide reciproca-ble on said support, meansfor precisely moving said slide toward and away from said wheel, a pivotbearing mounted on said slide, a pivot shaft mounted in said bearing, anarm connected to and depending from said shaft, a rest extendingtransversely from said arm into proximity to said wheel and having arelatively flat upper surface portion thereon, a template mounted onsaid rest, a wheel dressing tool holder having a bottom surface slidablyengageable with said upper surface portion and with said template, and awheel dressing tool mounted on said tool holder.

9. A wheel dresser for grinding machines comprising a support.attachable to the grinding machine, a slide reciprocable on saidsupport, means for precisely moving said slide toward and away from saidwheel, a pivot bearing mounted on said slide, a pivot shaft mounted insaid bearing, an arm connected to and depending from said shaft, a restextending transversely from said arm into proximity to said wheel andhaving a relatively flat upper surface portion thereon, a templatemounted on said rest, a wheel dressing tool holder having a bottomsurface slidably engageable with said upper surface portion and withsaid template, and a wheel dressing tool mounted on said tool holder,said pivot shaft having its axis inclined upwardly relatively to saidslide.

FERDINAND J. HENKEL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,324,937 Kropf July 20, 19432,137,690 Kropf Nov. 22, 1938 2,351,269 Kropf et al June 13, 1944

